[@Keksalot] Pardon me, I thought you hadn't read the wiki. My mistake. A vampire is, in a sense, basically a corpse possessed by its own ghost - there's a demonic virus involved that keeps the living corpse alive, and consequently powers it up and so on, but anatomically, vampires are pretty much identical to humans, save the bright red blood vampires have and a tendency to burn like kindling. That said, I think in this case it's safe to assume the wiki holds true: it does need to be a wooden stake to slay a vampire via heartstab, but as stated there, beheading a vampire or forcing it to bleed out completely does also kill them.

As for "moving the heart around" as opposed to "removing the heart", that's basically the same thing: the heart is essentially held in place by four separate major blood vessels, two of which lead to and from completely different areas of the body than the other two, meaning that to move the heart around the body would require also moving those blood vessels in a way that doesn't sever any of those blood vessels- because of the bleeding out, remember, which answers your question on how lethal heart removal is too- which so far as I can see is practically impossible in this setting. Along the same lines, the heart is a direct part of the circulatory system, as opposed to just being "attached to it", so sliding it somewhere else in your body doesn't exactly work out so well either. Furthermore, vampires, and for that matter werewolves, don't have their own demonic magic to call upon; it's just "in them", so to speak, as opposed to warlocks, who can use demonic magic, but evidently lack the physical power that vampirism grants, and even then, I can't say either way that any spell exists in setting which would allow one to move somebody else's heart around like that, or that any warlock (and/or surgeon, before you ask, mundane or otherwise) exists that would willingly cast such a spell (or surgically move the heart to another location).

Long story short, I don't think what you're asking for is particularly viable. It's a good thought, mind you, but you'll want to consider other options than that.